Grinding wheel dresser



R. E. PRICE I'AL GRINDING WHEEL DRESSER Decu 21, 1954 l INVENTOR RALPH E. PR/cf BY l-/POL B49 5/5 ATTORNEY 2t-6:92426 GRDENG WHEEL DRESSER Ralph E. Price, Highfield, li/id., and Harold E. Baisiger, Waynesboro, Pa., assignors to vLandis Tool Company, V/aynesboro, Pa.

Appnfaaan .time 22,1955, senat Ng. 1,169,665 5 claims. (ci. 12s-1i) This invention relates to grinding machines, particularly to apparatus for Vdressing the grinding wheel onsuch machines.

The invention relates more particularly to the dressing of grinding wheels having angularly related grinding surfaces. In the past, it has been necessary to use separate dressing devices, each positioned'at an angle in accordance with the angle of the wheel face which it was to dress.

I t is an object of this invention to provide a dressing device which will serve to dress both facesoflan anglefaced wheel.

A further object is to provide means for holding the dresser out of contactwith the grinding wheel during traverse in one direction.

The drawing is a diagrammatic sketch showing the essential elements of the invention.

Numeral 1o indicates a dresser housing for the diamond holder 11, on which are mounted in angularly spaced relation two diamonds 12 and 13 for dressing the faces 14 and 15 respectively of grinding wheel 16. Said diamonds are mounted in said holder at an angle to one another corresponding substantially to the angle between the faces of the wheel to be dressed. With this arrangement, each diamond is mounted in the position best suited to the wheel surface it is to dress. This dresser may be mounted in the fender of la grinding wheel. Axial adjustment oi said diamonds relative to said grinding wheel may be effected by an adjusting screw (not shown) in housing 10. Said screw may be turned by means of a ratchet 20 actuated by pawl 21 on piston 22. Said piston is reciprocaily mounted in a cylinder 23.

Housing may be slidably mounted in a slide 17 movement radially and axially of the grinding wheel. traversing movement of dresser housing 10 may for A be effected by piston 30 slidably mounted in cylinder 31 and connected to slide 17 by means of piston rod 32. The dresser housing 1d is moved'transversely of slide 17 as it passes across grinding wheel 16 by follower 4h in engagement with a template 41. Said template has a guide surface MA lorresponding to the surface 14 of grinding wheel 16 and a surface 15A corresponding to the v face of said grinding wheel. The wheel face 15 and the corresponding template face 15A are at such an kangle that it is diicuit for follower i6 to follow it during a traversing movement from left to right. For this reason,

2,697,426 Patented Dec. 21, 1954 slot v30 extending from the top of the piston to lwithin short distance' of the bottom.' Piston-51 has' aslot`p82 extending'from the bottom of the piston'to within 'a short distance of the top." A fluid vline S5 extends 'from cylinder 52 totheright e'nd of feed cylinder 23. Line`86 ezitendsfrom'cylinderSS to the left-hand end'ofcylinde'r Fluid supplied to the rod end of cylinder 31 must pass through a Vcheck valve 90." Exhaust from vthis end of the cylinder must pass through a throttle' valve 91 and'a check valve 92. Fluid to the head end of said cylinder must pass from line 75 through a' check valve `95. "EX- haust `fluid from the head end'l of "cylinder 31 passes through throttle valve 96 and check valve 97. Said check valves are held closed by springs having suicient force tol prevent opening thereof until pistons Strand 51have acted.

lOperation In the ,position .shewn. ,dresser housing 10 .has just Completeda Workinststrokeacross the faces `14jand .1.;5

of wheel 1.6. IIn order to vreturn it tooriginal position,

switch 101) is opened to deenergizesoienoid A101. Spring 102 shifts valve63 to the right to direct uid kunder pressurefrom line 62 through lines 64 and 7 5 and check valve 9S to the head end of cylinder 31 to shift slide z17 i nddresser housing 10 to the right. At the same time,

4fluid is directed throughllines' 76 and 77 to the (lower ends of cylinders S2 and yS3 to move dresser housingl 1 0 `fransvers'ely away from grinding wheel y16.y The fluid directed to cylinder `53 passes through slot 82, "line" 86 to the left end ofcylind'er4 23 and shifts piston 22 and pawl `21 ythe circuit through switch 1 00 to solenoid 101, ,shifting it is necessary that the dresser 'oe withdrawn to a posif tion where it can be traversed from left to right without engaging the grinding wheel.

The means for effecting this withdrawal movement consists of a pair of pistons and 51 slidably mounted in cylinders 52 and 53. Piston rods 54 and 55, extending v from the top of said cylinder, are attached to bar 58 or any other suitable means attached to or forming part of dresser housing 10.

Fluid under pressure for operating the various pistons is suppliedtby pump 60 having a relief vaive 61 attached thereto. Said pump directs fluid through line 62 to reversing valve 63, which in turn directs fluid alternately through lines 64 and 65. Line 65 is connected to line 70 to direct uid to the rod end of cylinder 31 and also to the upper end of cylinders 52 and 53. Cylinder 52 is connected to line through line 71. Line 64 is connected to the head end of cylinder 31 through line 75 and also through lines 76 and 77 to the lower ends of cylinders S2 and 53 respectively. The connection to the lower end of cylinder 52 is through line 76. Piston 50 has a 14 of grinding wheel 16.

valve 63l to the `left and directing Huid through line to line 7i).^ In' actual practice, thisreverse is'automatic. Manual reversing isdescrib'ed here Vfor ythe purpose of v a simplified illustration. AVFrom line 76, fluid entersthe upper end Aof'cylinders 52and53 to move pistons 5,0 and 51 downward to a position to locate dresser housing v10 transversely in operative 'relation'A to the grinding wheel.

Fluid directed to the upper'end of cylinder y52 passes through slot S0, line `to the right end of cylinder- 2.3, shifting piston 22 and'pawl 21 to the left to rotate ratchet 20 and dresser feedscrew 18 to advance diamond'holder y11 for the next pass across wheel 16.

Fluid also passes through line"`70 `and check valve to the rod `end of vcylinder`31 to rnovev piston 30 therein and dresser housing 10 `to the left. Movement of piston30 from right to left must be at a rate suitablefor dressing. Exhaust fluid from the he'adendof cylinderl must pass through valve `96,`which controls the rate of this movement.'l This valve is set so as to provide a cornparativelyvslow movement suitable for a dressing operation. During this movement, follower 40 rides along face .14A`of template 41 to guide diamondw12 along face l Said follower lifts diamond holder 11 against the pressure in thetops of cylinders'SVZ and 453. When said follower reaches 4the top of 'surface 14A, it must pass across a dat portion 110, which p ermits it to travel to ya point at `which diamond ,13, willvbe in position to dress face 15,01:` the grinding wheel.' At this ,Point .the .follower .begins Vto move downwardly `on surface 15A of the cam bar; and diamond 13 passes across face 15 of the grinding wheel.

It is desirable that the traverse movement of the dresser during the period after the completion of dressing of grinding wheel face 14 and prior to the dressing of face 15, that is, while follower 40 is passing across surface 110, take place at a higher rate of speed than the dressing movement. One means for accomplishing this result consists of a cam attached to bar 5S and having an operative surface of a length corresponding to the surface 110 of template 41. When rollower 40 reaches the end or surface A and the beginning or surrace 11u, cam 1z0 engages a lumt switch in to complete a circuit trom L1 through valve solenoid lu and line 1 2. bald solenoid shirts uy-pass valve 14.5 so that exhaust l'luld from the head enu or' cylinder .u passes through said by-pass valve to exhaust through lines '/o and o4 and reverse valve 63 instead or passing through throttle valve 96. This portion or' the traverse movement, therefore, occurs at a rapid rate. when follower 4u reaches the end or' surface 110, cam 120 releases limit switch 111, deenergizing solenoid 1u so that spring 124 returns said valve to its original position, ln which the by-pass is closed. Exhaust nuid from the head end of cylinder 31 must again pass through throttle valve 9o, which reduces the traverse movement to a rate suitable for dressing the face 15 of grinding wheel 16.

We claim:

l. A grinding wheel having angular peripheral faces and a wheel truing apparatus therefor, comprising, a slide movable in a direction axially of said grinding wheel, a diamond holder mounted on said slide for movement transversely thereto, diamonds in said holder substan tially 180 apart and inclined relative to the axis of said holder at an angle to one another equal substantially to the angle between said grinding wheel faces whereby one of said diamonds will engage one of said faces, and the other of said diamonds will engage the other of said faces, means responsive to movement of said slide for effecting said transverse movement of the diamond holder including a template, a follower attached to said diamond holder and yieldingly held in engagement with the contour of said template during said movement of said slide, said template having inclined surfaces corresponding to the angular faces of said grinding wheel, a llat horizontal surface between said angular surfaces equal substantially to the space between said diamonds whereby to permit an idle traverse movement of said diamond holder after dressing one of said wheel surfaces by one of said diamonds and before starting to dress said other wheel surface by the other of said diamonds.

2. A grinding wheel having peripheral faces and a wheel truing apparatus therefor, comprising, a slide movable in a direction axially of said grinding wheel, a diamond holder mounted on said slide for movement transversely thereto, diamonds in said holder substantially 180 apart and inclined relative to the axis of said holder at an angle to one another equal substantially to the angle between said grinding wheel faces whereby one of said diamonds will engage one of said faces, and the other of said diamonds will engage the other of said faces, means responsive to movement of said slide for effecting said transverse movement of the diamond holder including a` template, a follower attached to said diamond holder and yieldingly held in engagement with the contour of said template during said movement of said slide, said template having inclined surfaces corresponding to the angular faces of said grinding wheel, one of said surfaces being too steep for the follower to move upwardly thereon in response to the longitudinal movement thereof and means for withdrawing said dressing tool from engagement with the grinding wheel when said dressing tool moves toward said steeply inclined surface.

3. A grinding wheel having peripheral surfaces at an angle to one another, one at a relatively steep angle, and means for dressing said surfaces, including a diamond holder movable toward and from said grinding wheel and ha"ng diamonds mounted thereon in angular relation cor esponding to that of the wheel surfaces, means for trav rsing said diamond holder relative to said wheel, including a hydraulic motor, a supply of lluid under pressure for said motor, a reversing valve for directing said fluid under pressure alternately to opposite sides of said motor, hydraulic means for moving said diamond holder toward and from said grinding wheel including a template and follower yieldingly held in engagement with one another, one of which is attached to said diamond holder and traversiole therewith, said template having one guide surface which is inclined too steeply to permit me passage of said follower in one direction, connections between said reversing mechanism and said hydraulic means whereby said hydraulic means is elreetive to position said diamond holder transversely in operative relation to said grinding wheel when huid under pressure is directed to one side of said traverse motor and to withdraw said diamond holder to an inoperative position when said lluid is directed to the opposite side of said traverse motor.

4. A grinding wneel having peripheral surfaces at an angle to one another, means for dressing said surfaces, including a diamond holder movable toward and from said grinding wheel, means for traversing said diamond holder relative to said wheel including a hydraulic motor, a source of fluid under pressure connected thereto, a template having angularly related surfaces corresponding to the faces on said grinding wheel, a follower on said diamond holder engaging said template, a diamond on said diamond holder for engaging one face of said grinding wheel when the follower engages the corresponding face of the template and a second diamond on said diamond holder for engaging another face on said grinding wheel when said follower engages the corresponding surface on said template, a horizontal surface on said template between said faces corresponding to the space between said diamonds, and means for increasing the traverse speed during the passage of said follower along said horizontal surface including a valve for controlling the supply of fluid to said hydraulic motor, and a cam movable with said follower for actuating said valve.

5. A grinding wheel having peripheral surfaces at an angle to one another and means for dressing said surfaces including a diamond holder movable transversely toward and from said grinding wheel, means for traversing said diamond holder relative to said wheel, means responding to said traverse movement for effecting said transverse movement, including a template having angularly related surfaces corresponding to the surfaces on said grinding wheel, a follower yieldingly held in engagement with said template, a diamond on said diamond holder for engaging one face of said grinding wheel when the follower engages one face of the template and a second diamond on said holder at a predetermined angle to said rst diamond for engaging another face on said grinding wheel when said follower engages the other face on said template, and a horizontal surface on said template between said faces for holding said diamond holder in an inoperative position while traversing from operative position for one diamond to operative position for the other.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 689,845 Barrow Dec. 31, 1901 840,876 Steedman Jan. 8, 1907 2,150,091 Alvord Mar. 7, 1939 2,248,463 Ott July 8, 1941 2,292,947 Kasparson Aug. 11, 1942 2,323,401 Johnson July 6, 1943 2,340,683 Price Feb. 1, 1944 2,373,187 Johanson Apr. 10, 1945 2,447,478 Rundt Aug. 17, 1948 2,458,444 Stewart Jan. 4, 1949 2,465,580 Ernst Mar. 29, 1949 FOREIGN PATENTS Number Country Date 490,776 Great Britain Aug. 22, 1938 541,801 Great Britain Dec. 11, 1941 

